Soldering is a process in which two or more metal substrates are joined together by melting and flowing a filler metal into the joint, the filler metal having a relatively low melting point. In a conventional soldering process, heat is applied to the substrates to be joined, causing the solder to melt and be drawn into the joint by capillary action and to bond to the substrates to be joined by wetting action. A solder flux agent or material is typically used to assist the flow of the solder into the desired location.
Metal substrates may alternatively be joined together using polymeric adhesive materials. Conventionally, this is done by applying the adhesive between the metal substrates. The substrates may also be fastened in a similar manner to a conventional soldering process.